It is a test please help Which organ is not connected to its system?

a) Spinal cord – Nervous system

b) Large intestine – Digestive System

c) Testes – Reproductive system

d) Kidney – Circulatory system

They are both used to view parts of the cell

The answer would be generation

Mars and earth have quite a few things in common. both are  terrestrial planets, both are located within the sun’s  habitable zone, both have  polar ice caps, similarly  tilted axes, and similar  variations in temperature. and according to some of the latest scientific data obtained by rovers and atmospheric probes, it is now known that mars once had a  dense atmosphere  and was covered with  warm, flowing water.